Such a soil-working farm machine is known the connecting rods of which serving to transmit the reciprocating movement to the corresponding bar are relatively short and are connected to the corresponding bar by a yoke fastened to the end of the bar extending close to the connecting rod-eccentric device. Each yoke extends upward from the corresponding bar. Each connecting rod has a small end connected to its corresponding yoke by means of a connection with an axis directed at least approximately parallel to the forward direction and a big end connected to its corresponding eccentric.
The known device, however, has a number of drawbacks.
First, to insure that the connecting rod-eccentric device cannot be soiled, it must be located relatively high, far from the worked soil. Therefore, the connecting point of a connecting rod to its corresponding yoke is also located relatively high, which means that the height of the yoke is relatively great.
Second, because of the great forces that each connecting rod is to transmit to its corresponding yoke to drive its corresponding bar, there appear, after the machine has been in use for a while, breaks of the bar at the spot where the connection of the yoke to the bar stops. To avoid these breakage problems with the known design would require such a reinforcement of the bars that their weight would be unacceptably increased.